From The Denver Post (Clayton Woullard):
After one year of operation, the Plum Creek Water Purification Facility has exceeded Castle Rock’s expectations in terms of efficiency as it plays an important role in the town’s long-term renewable water projects. The $22.6-million-dollar plant went online in April 2013, specifically to treat more ground water, as well as renewable surface water from Plum Creek. The facility is part of an effort by Castle Rock to have 75 percent of its water come from renewable sources by 2050, when the town projects it will be built out at 100,000 people. The town’s population is at about 53,000 now.
Other parts of the project are a renewable water agreement through the Water, Infrastructure and Supply Efficiency partnership (WISE) with Denver Water and Aurora Water, as well as storage of 8,000 acre feet of water in Rueter-Hess Reservoir in Parker. Castle Rock Utilities Director Mark Marlowe said the plant’s operating costs, along with the WISE partnerships, are coming in under budget.
“If we don’t do these things, we continue to be reliant on our deep water supplies,” Marlowe said.
That’s something the town and other Douglas County jurisdictions can’t afford, because well water continues to be depleted.
The WISE partnership agreement is almost complete, Marlowe said and will eventually bring about 7,225 acre feet of renewable water and 1,000 acre feet in the short term to Castle Rock. Marlowe said two contingencies must be finished by next year to get WISE water flowing: the $4 million purchase of a pipeline that will get water from Denver and Aurora to Castle Rock; and a new pipeline the town will need to allow it to begin receiving renewable water.
Marlowe said the water supply from WISE is interruptible, unlike the supply coming through the treatment facility.
The Plum Creek Purification Facility captures water from East and West Plum Creek and lawn irrigation return flows. The plant treats more than 4 million gallons of water per day but has the capability to treat up to 12 million gallons when it is eventually expanded. The plant has the capacity to bring the town 35 percent renewable water; now it’s between 12 and 20 percent renewable, depending on demand.
“It is exciting for our community that we get to use this resource,” said Karen McGrath, spokeswoman for the town.
Because the plant also treats surface water, it has different processes, including a series of racks or tubes of thousands of very thin, vertical membranes that filter the water and require regular maintenance and cleaning. Marlowe said surface water requires more treatment than ground water and necessitated the facility.
Most of the plant’s processes run automatically, so the plant only requires about two workers at any time. The system is set up with alarms and auto-correcting mechanisms.
Level 4 plant operator Ken Timm said it’s the most advanced water treatment plant he’s worked at.
“The only challenge is if something breaks,” Timm said, “and how fast can we get it repaired and what caused it.”
More Denver Basin Aquifer System coverage here.